Japanese cedar

Thousands of Japanese cedars were planted in Japan in the 17th century. One resulting avenue of trees still exists today, measuring 65 km in length, with trees growing to an impressive 70 m in height.

About Kew's Japanese cedar trees

Kew's tradition of planting sequentially according to taxonomic arrangements means this is the right spot to plant these Cupressaeae. But with so many extremely large members, this family illustrates well one of the problems with Kew's system. We may need to work hard to manage soil conditions to suit a planting or, as in this case, seriously limit numbers to ensure each specimen has enough room to grow.

Take a closer look

In Redwood Grove you can compare the foliage of the Japanese cedar to that of the similar giant sequoia, Sequoiadendron giganteum. Both have needles arranged spirally around the leaf shoots, but those on the Japanese cedar are longer.

The cones of the Japanese cedar are smaller than those of the giant sequoia and have a number of distinctive curved spines on each scale. They take a year to ripen fully, at which point they are dark brown and woody.

Tree biology

The Japanese cedar, the national tree of Japan, is not a true cedar. It is closely related to the giant sequoia and shares many characteristics, not least its impressive size and lifespan.

It is also found in China where it may have been cultivated as opposed to being native but if so, it has been cultivated there for so long it is hard to know for sure.

Although revered in Japan, it has its drawbacks. When the male flowers shed their pollen from February, it can trigger hayfever and asthma.

Cultivation and uses

The wood of the Japanese cedar is fragrant, reddish-pink in colour, lightweight but strong, waterproof and resistant to decay. It is favoured for all types of construction work and has been used in this way in China and Japan for centuries.

Unusually for a conifer, it can be coppiced (cut down near the ground to encourage new shoots). However, in Britain it is regarded almost exclusively as an ornamental.